1. Field of the Invention
This invention relates generally to the field of multiple channel selection and picture display in a wide screen television, wherein a main video picture and a plurality of secondary video pictures can be displayed as POP's, and more particularly, wherein the secondary pictures can represent a viewer selected set of available video pictures from which the main picture can be frequently and/or continuously selected and reselected by the viewer without having to reidentify channel numbers or the like. This facilitates quick and convenient monitoring of a plurality of signals such as sporting events, soap operas, newscasts or the like, in which the most interesting action of simultaneously broadcast is programs may occur in the different programs at different times.
2. Description of Art
With the advent of wide screen televisions, many new features are made possible. A wide screen television may have a format display ratio, for example, of 16 horizontal units and 9 vertical units, as opposed to the traditional television display ratio of 4.times.3. One feature made available by the wide screen display ratio is the POP, or picture-outside-picture feature. POP involves the display of one or more smaller video images in an otherwise unused side area of the 16.times.9 display area, simultaneously with display of a larger 4.times.3 image.
The main 4.times.3 image, from a first source, is arranged to the available vertical space. By placing the main 4.times.3 image at one lateral side of the display area, sufficient space is opened along the opposite side for up to three more images, each having a 4.times.3 display ratio and being one third of the size of the main 4.times.3 image. It is also possible to use other specific ratios and display arrangements; however, by making the three smaller images one third of the size of the larger one, no cropping, uneven compression or other distortion is needed for any of the images contained in the first (main) source signal, or in the images contained in the signals from second through fourth sources, used for the pictures outside of the main picture. Presently available products allow either one channel to be strobed through the three extra POP windows, or for the extra windows to be used to display images from the sequential tuning of channels in a scan list.
A wide screen television apparatus with POP capabilities is known from WO/19388, published Dec. 12, 1992, corresponding to International patent application PCT/US91/03740, filed May 29, 1991. The television apparatus a one chip video processor and two tuners. A wide screen processor controls the use of the display for the main picture, decoded using one of the tuners, and one or more supplemental POP's (or PIP's, i.e. picture-in-pictures), decoded using the other tuner. Where a plurality of supplemental pictures are provided, the second tuner sequentially selects one of the required frequencies and the wide screen processor grabs an image. The display is then driven to present the main image and the most recently captured frame(s) of the supplemental image(s). Although the device operates continuously to update the images, due to the sharing of the second tuner the supplemental pictures are necessarily updated at less than their video rate. The wide screen processor resolves any differences in synchronization between the images.
A system of this type, for cycling through channels in several small images, is also described in the publication entitled The CTC 140 Picture in Picture (CPIP) Technical Training Manual, available from Thomson Consumer Electronics, Inc., Indianapolis, Ind.